Generation of CAR T cells targeting MUC-1 and tested in a MUC-1-expressing breast cancer xenograft mouse model showed that MUC-1-CAR-T cells significantly reduced tumor growth compared to untreated control mice by promoting T cell proliferation and increasing production of inflammatory cytokines such as IFN-γ, resulting in enhanced antitumor immunity and the killing of MUC-1 positive tumor cells [125]. Here, MUC1 is linked to breast cancer.